The Aracne server uses a pool of reusable threads to manage the
execution of concurrent tasks. The parameters that can be configured are
as follows:

Default number of threads. Intuitively, this parameter indicates
the number of threads the system should have active at the same time
in normal load conditions (20 by default). Whilst there are fewer
threads than this number in the pool, new threads will continue to be
created. When a thread is requested and the number of threads in the
pool is the same as or more than this value, inactive threads are
reused, if they exist; otherwise, new threads will continue to be
created until obtaining the value established by the next parameter.

Maximum number of threads. This represents the maximum number of
pool threads (60 by default).

Keep alive timeout (ms). This specifies the maximum time in
milliseconds that an inactive thread remains in the pool if the total
number of threads exceeds that indicated in “Default number of
threads” (0 by default). If the value is 0, the threads created above
this value end, once the execution of their task has been completed.
Otherwise, those which exceed the time specified in this parameter
are removed from the pool.